Falling saw



1s, 1945. c. WOLF 2,391,286

FALLING SAWv Filed Jan. 18, 1943 Patented Dec. 18, 1945 ED STATES PATENT oFFlcEJ g 2,391,286 FALmNG saw a j leliarlcswclf, Peruana, ereg, Application January 1s, 194e, scm-mc. 412,710

` Y s claims; (01.143-135) This' invention relates generally to chain saws, and'particularly to a falling saw.

, The main object of this 'invention is to con'- struct an improved form of falling sawl of the general' class illustrated in my cci-pending patent s application, vSer'. No. 328,62'7' over which the saw described herein is an improvement. due to its greater sawdust carrying capacity, lesserweight per foot of chain length, less material" rewqizlifrediin the manufacture ofthe raker teeth,and.th'e elimination of the tendency' or saw dust to wedge kundeimtl'le trailingpraker tooth bythe elimination of the trailing toothitself.

The secondV object' is to construct a saw of the class described which will be especially adapted for fallingjowing to a dennite relationshipv between the clearance of the saw' in the cut,l andv the tolerance permitted in the fits between the saw chain and they frame Vupon which it isV mounted.

The third object is to construct' a falling saw of' the Ychain type in which theinteraction between the saw frame and the saw chain is so advantageous as to' minimize the wear which normally koccurs in the parts thereof'.

The fourth object is'fto'A construct a saw of the .class described in which rthere will be a material ytendency vfor the saw .to vcut in a. straight horizontal plane. n v

The fth object iste construct a sawof: the' class described in which the under sides of the lowermost cutter teeth serve to rest'uponthe lower side of the sawY slot and to have their innermostr intermediateV point serve as a point ofcontact. with the frame itself) whereby` 'the pressure per square inch on the wearing parts ris reduced toa. minimum.

The sixthjoloiect is to construct a falling saw'of' the class described whereinthe chain is permittedl to rock transversely on the transporting' frame without setting up itself,"thereby enabling' thechain to form a: sube stantially' horizontal cutin e; straight plane.

isi to yadd to the life of the" The seventh object' saw by reducing the wear on 'the chain rand frame due to the free running action of the parts thereof.` r

"nie eighth object is to so 'relate' the saw frame and chain that the length 'ofthe'cutter link constitutesa 'beam supported at' both ends against the sides of the saw cutiwhle the' load from the framere'sts between the supported ends;

.'Thenl'nth'obj'ect is to eliminate the 'spreading action commonly found.' '1n'. saws of' the chain type.

These' and` other.

a binding' action on the frame" obiects are accomplished in 5a the manner set forth. in the following specinca- Vticmas illustratedin the accompanying drawing,

in which:

Fig. 1 is a iragmentarysection through a short length of chain sawv and its supporting traine, showing'a portion of a saw slot'inse'ctoll.

Fig. 2` is a section taken along they line 2-2 in Figi. I.

`Fig. 3 is a transverse section taken along the line 3---3l in Fig. I.

Fig. 4 is a view similar to Fig. 3but showing a prior art condition.

Similar numerals refer to similar' parts throughout the several' views.

Referring= n detail to the' drawing, there is shown a saw frame lill having, a narrow track lt formed thereomwhose sides l2 are parallel and whose edge i3' is preferably rounded as' shown.

The saw chain itself.v consists of. pairs of cutter links ld and [5' which are identical' in form and; are used right and` left in order that the teeth i6 and. I1' will' not be opposite eachother-hat is, the teeth I6 and l1 are not midway between the. holes lllv in which are riveted". the reduced ends I9' of the rivet bodies 20.

Each. cutter link I4 and f5' has a somewhat roundedbase 1l' which. conforms to the rounded end' of the saw frame (not shownl'",= its function. being to support the. chain onits turns.

3o, I`t willv be noted that the curved bases 2l :trev

remote from the shoulders 224 ofv the frame Ill,-

'being intended. that they shall never come iii contact..

. It will also be notecL, that the links ll ac l5 are held apart by the rivet. bodies'zll to providev what appears to be an abnormal clearance 234 between the inner faces 2li'4 and. the outer faces l2 ofthe track Il.A The teeth I`6 and l1 areprovided 4with cutting points 25. The puirpose` of the 4cL clearance 23 will be set forth presently,

Raler links 26' are .provided With holes' 2T to receive the` rivet bodies 211,. and thereby connect' the cutter links in a manner which'is well understood". The raker4 links 26' are elongated "to` 45;. form a base 2s" which extendsbeyond the rivet holes 2T foru reasons 'set forth in the co-pending application above id 'ntedl Each raken link 26" is provided with a' raken tooth 29, whichi is offset in parallelism with Vthe lside of the raken linl:

i set is used to describe' thev parallel conditionerr the raker tooth withrelation toy the raken link as opposed. to theusual angular set of the points' It will be' noted that the chisel shaped point W o. itself. It' will be understood 'that' the term lfoif' of each raker tooth 29 is extended to the raking line 3| which is somewhat back from the cutting li-ne 32, the separation of these lines depending upon the kind of wood being cut, speed of operation, and other factors.

An inspection of Figs. 1 and 2 discloses the fact that there is a tortuous channel formed between the cutter teeth I5 and I1 and on the sides of the raker links 26.

In the presenti instance, the cubical capacity of this channel 'is increased over the type shown in the co-pending application, due to the fact that there is but one raker tooth 29 on each raker link 26, and the action is further improved by the fact that when two raker teeth are employed on a given link for the purpose of making the saw reversible, the trailing 4link obviously aiords a V shaped pocket into which particles can wedge.

While the raker tooth point 3U is illustrated as being chisel shaped, it is obvious that this can assume any other form without departing from the spirit of the invention.

It will be `noted that the intermediate portion 33 of each raker link base 28 is curved on a somewhat larger radius than are the curves 2| in order t'o enable same to pass around the corresponding portion of the track II. It will also be noted by referring to Fig. 3, that each link 26 has its base l28 rounded to conform to the rounded edge I3 'of the track II in order to permit a limited amount of rocking by the chain on`the track I I, and it will be noted in Fig. 3, which represents a falling cut, that the saw frame I0 does not rest upon the bottom 34 of the cut being formed in the log 35i-A, but it does rest upon the intermediate point of the side 24 of the cutter link I5 whose point 25 and base 36 rest against the cutside 34, enabling the track II 'to hold the'saw chain in an ideal and free running relationship vat all times, and importantly, to hold the point 25 accurately to the plane of the cut side 34.

` Referring now to the prior art condition illustrated in Fig. 4, in which the chain does not straddle the track but inwhich the raker link 40 is provided with a base ilv which extends into the raceway 42 and in which the frame 43 rests against the lower side 44 of the cut 45 being formed injthe log i5-A. Here a diiierent condition exists in which the base 4I of the raker tooth 40 attempts to spread apart the sides 46 of theframe 43. In-su'ch saws, the clearance between the frame members 46 and the raker tooth'base 4I is held to a minimum, and the bottom 41 of the base 4I bears against the bottom 48 of the raceway 42.

In this form of the device, the cutter links 49 have their bases'i) bearing against the track edges 5I on each side of the raceway 42. However, as the cut proceeds, and the weight of the sawframe 43 rests upon the surface 44, the low-v ermost cutter teeth 52 which are remote from the bases 5%, exert a leverage against the wearing surface bringing about a wearing condition shown lin Fig. 4, which condition is aggravated by the fact that the contact between the membersl 5i! and 5I on the top side of the frame 43 serves as a fulcrum to increase the spreading action. As this wear develops, it permits the saw chain to leave its normal cutting plane 53 and cut `a curved .line as shown; and while this alone is only slightly objectionable, the serious objection resides in the fact that the following of this curved cutting line continues to maintain the wearing action on the parts until the saw itself is destroyed. In the meantime, an objectionable amount of power has been consumed in driving the saw instead of being employed in actual sawing.

It will be noted that by straddling the track as shown in Figs. 1 and 2, and providing an excessive clearance on the sides of the track and further shaping the raker link bases so as to encourage transverse rocking on the track, that the saw is not only made to operate with the least amount of effort, and internal stress, but

Aalso there is provided a relatively great amount of clearance for sawdust. Not only does the chain itself act as a cutting conveyor, but the space between the link bases 2| and the shoulder 22 also alfords a passageway for dust. Furthermore, the use of a single tooth increases the clearance for sawdust, eliminates the wedging action of the dustunder the .trailing tooth, and lightens the chain itself; and the life of the chain is not halved by the reduction inr the number of raker teeth sincethe teeth which are employed operate to the best advantage. The elements herein described are so inter-related and dependent upon each other as to require their joint use to obtain .theV maximum amount of utility from the device.

I'claim: y

'1. A falling saw having in combination a transversely Vconvex track, a block link saw chain having pairs 0f side links straddling the track and having the track engaging edges of the block portions transversely concaveV to lit said track, the clearance between the outer sides of the track and the inner sides of the side links being suiiicient to permit the lowermost of said side links to ride upon the under side of a cut while the outer edge only of the track portion rests upon the top sides of the lowermost cut engaging links while the 'saw is in a tree falling position.

2.' In a falling saw, the combination of a longitudinal frame, around which frame is formed a narrow endless track. the outermost edge of which is transversely convex. a s'aw chain straddling said' track whose width'is substantially wider than the thickness of said frame and whose track engaging portion is transversely concave to fit said track. said track and chain having excessive l'ateral clearancebetween same adapted to permit Ithe chain to rock laterally a limited amount on said track.

3. A 'falling saw having a transversely rigid' upon said track in `order that the points and thel opposite edges of the lower cutting links may rest upon thel bottom of the cut while the points only of the upper cutterflinks engage the top ofthe cut,vand wherein the underside of the outermost track portion only rests upon the upper' sideof the lowermost cutter links, while the frame is spaced from the sides of the cut.

4. A falling saw having a transversely rigid elongated frame, a narrow gauge track formed along the edge of said frame and thinner than is said frame, a saw chain having elongated raker links thicker Ythan is said track and slidable thereon, each of said raker links having one forwardly inclinedv raker tooth extending there-r from, pairs comprising upper and lower cutting teeth links uniting said raker teeth links and having portions thereof extending along the sides of the track and normally spaced therefrom, the contacting portion of said track and raker teeth links being curved transversely, that of the track being convex and that of the raker teeth links being concave, whereby the chain is enabled to rock transversely a limited amount upon said track in order that the points and the opposite edges of the lower cutter links may rest upon the bottomvof the cut while the points only of the cutter links engage the top of the cut, and wherein the under side of the outermost track portion only rests upon the upper side of the lowermost cutter links while the frame is spaced from the sides of said out.

5. A falling saw having a frame adapted to pass freely into the saw cut, a narrowr gauge track of less width than said frame disposed around the' lateral edge of the frame, elongated raker teeth links disposed around said track and exceeding same in thickness, pairs of cutter teeth links joining opposite sides of said raker teeth links and straddling said track in a manner to provide a substantial amount of lateral clearance for the purpose of permitting a limited amount of lateral rocking of the chain, the contacting edges of said links and track being respectively convexly and concavely curved to match each other, said cutter links having their teeth set to flare outwardly in a manner such that the points and opposite edges of the lowermost cutter teeth of the saw will ride on the bottom of a horizontal cut while only the outermost portions of the track will rest upon the top sides of the lower cutter teeth between the points and bases thereof.

6. A falling saw having a frame adapted to pass freely into a saw cut, a narrow gauge track of less thickness than has said frame, disposed along the lateral edge of the frame, elongated raker teeth links disposed around said track and exceeding same in thickness, each of said raker 'teeth links having a forwardly inclined raker tooth projecting therefrom, pairs of cutter links joining opposite sides of said raker links and straddling said track in a manner to provide a substantial amount of lateral clearance for the purpose of permitting a limited amount of lateral rocking of the chain, said cutter links having their teeth set to liare outwardly in a manner such that the points and opposite edges of the lowermost cutter teeth of the saw will ride on the bottom of a horizontal cut while only the outermost portions of the track will rest upon the top sides of the lower cutter teeth between the points and bases thereof, the contacting edges of said links and track being transversely curved onr a radius lying within the cutting plane and on the track side of the links.

CHARLES WOLF. 

